readme.md

Encryptor

Need to encrypt/decrypt something real quick? This is a simple, dependency-free way to get the job done.

const { encrypt, decrypt } = makeEncryptor('my-secret-key')

encrypt('hello, world!') // -> 1d1019191a5955021a07191154
decrypt('1d1019191a5955021a07191154') // -> hello, world!

Credits

The majority of the code was taken from this SO answer.

encryptor.ts

export function makeEncryptor(key: string) {
	const textToChars = (text: string) => text.split('').map(c => c.charCodeAt(0))
	const byteHex = (n: number) => ('0' + Number(n).toString(16)).substr(-2)
	const applyKeyToChar = (code: number) => textToChars(key).reduce((a, b) => a ^ b, code)

	function decrypt(encoded: string) {
		return (encoded.match(/.{1,2}/g) || [])
			.map(hex => parseInt(hex, 16))
			.map(applyKeyToChar)
			.map(charCode => String.fromCharCode(charCode))
			.join('')
	}

	function encrypt(text: string) {
		return textToChars(text).map(applyKeyToChar).map(byteHex).join('')
	}

	return { encrypt, decrypt }
}